Draft control for furnaces and the like



April 30, 1929. F|RESTQNEIL 1,710,695

DRAFT CONTROL FOR FURNACES AND THE LIKE Filed June 8, 1928 INVENTOR James J? flreatme WWW Patented Apr. 30, 1929.

UNITED STATES PATENT OFFICE.

JAMES F. FIBESTONE, OF DOWAGIAC, MICHIGAN, ASSIGNOR TO THE BECKWITE COM- PANY, OF DOWAGIAC, MICHIGAN.

DRAFT CONTROL FOB FURNACES AND THE LIKE.

Application filed June s, 1928. Serial No. 283,753.

The main object of this invention is to provide a draft control for the flues of furnaces, boilers and the like which effectively holds the desired strength of draft during both firing and banking periods.

A further object is to provide a structure having these advantages which may be quickly adapted to accomplish the above results under varying weather conditions, by the use of various fuels, and the like.

. Objects relating to details and economies of construction and operation of my invention will appear from the description to follow. The invention is defined and pointed out in the,claims.

A structure which is a preferred embodiment of my invention is illustrated in the ac companying drawing, in which: a

Fig. l is adiagrammatic view illustrating my improvements as embodied in a warm air furnace.

Fig. 2 is an enlarged detail view partially in section on a line corresponding to line 22 of Fig. 3.

Fig. 3 is a detail elevation looking from the right of Fig. 2.

Referring-to the drawing, 1 represents a warm air furnace, 2 the smoke flue thereof, and 3'the thermostatically .controlled damper actuating mechanism operatively associated with a thermostat 4. These several parts are shown conventionally as the details thereof form no part of this invention except as hereinafter pointed out. 7

The smoke flue 2 is provided with a branch 5 having a check draft inlet 6. This inlet 6 is provided with a damper or closure 7 pivoted at 8 at its upper end to swing inwardly under the action of the draft, that is, it is automatically opened by the draft in the flue.

The damper 7 is provided with a counterweight arm 9 which projects above the pivot 8 and is provided with an adjustable counterweight 10. This counterweight provides 5 means for balancing the damper.

I am aware that counterbalanced draft opcrate-d dampers have been used to some extent but they do not accomplish the results of my improvements for the reason that they are to not adaptable to varying firing and atmospheric conditions.

To insure a positive control for the damper,

I provide a weight 11 which is suspended by a chain or cable 12 for sliding engagement is with the inner side of the damper and for adjustment toward and from the pivot of the damper. This adjustment is preferably done automatically as in the embodiment illustrated, the actuating mechanism 3 having an actuated lever 13 to which the cable 12 is connected.

. The furnace ash-pit draft 14 is connected bythe cable 15 to the other end of the lever 13 so that the draft 14 and the weight 11 are alternately actuated. r

I have illustrated and described my improvements in a simple and practical embodiment. I have not attempted to illustrate or describe various other embodiments or adaptations which I contemplate as it is believed the disclosure made will enable those skilled in the art to embody or adapt my in1- provements as-may be desired.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. The combination with a heater provided with a flue having a check draft opening, of a damper for saidopening hinged at its upper edge to open inwardly, a counterweight arm on said damper provided with an adjustable counterweight, a closing weight for said damper disposed to slidably engage the inner side thereof, a thermostatically controlled actuating mechanism, and a supporting cable. for said weight operatively connected to said thermostatically cohtrolled actuating mechanism.

2. The combination with a heater provided with a flue having a check draft opening, of a damper for said opening hinged at its upper edge to open inwardly, a closing weight for said damper disposed to slidably engage the inner side thereof, a thermostatically controlled actuating mechanism, and a supporting cable for said weight operatively connected to said thermostatically controlled actuating mechanism. 1

3. The combination with a heater provided with a fine having a check draft opening, of a 100 damper for said opening hinged at its upper edge to open inwardly, a counterweight arm on said damper provided with an adjustable counterweight, a closing weight for said damper disposed to slidably engage the inner per edge to open inwardly, a closing weight for said damper disposed to slidably engage the inner side thereof, and a supporting and adjusting cable for said weight.

5. In an apparatus of the class described, the combination of a .flue having a check draft opening and a coacting damper, a weight supported independently of said damper to be lowered into engagement with the inner side thereof, and a thermostatically controlled mechanism for raising and lowering said weight.

6. In an apparatus of the class described, the combination of a flue having a check draft opening and a coacting damper, a weight supported independently of said damper to be lowered into engagement with the inner side thereof, and means for lowering said weight. n

7. In an apparatus of the class described, the combination of a flue having a check draft opening, an inwardly opening closure therefor hinged at its upper end, and a weight slidably engaging the inner side of said cloopening, a closure for said opening provided with horizontal pivots and arranged so that the draft acts to open the same, a Weight disposed on the inner side of said damper and acting to urge it to closed position, and means for raising and lowering said Weight.

9. In an apparatus of the class described, the combination of a flue provided with a check draft opening, a draft actuated closure for said opening, a Weight adjustably associated with said closure to urge it to closed position, and a thermostatically controlled mechanism for adjusting said weight.

In witness whereof I have hereunto set my hand.

JAMES F. FIRESTONE. 

